The memcmp function compares the count bytes starting at s1 with the count bytes beginning at s2 .

Parameters

s1 and s2 are addresses of memory buffers at least count bytes in length.

Return Value

If the bytes at s1 are lexicographically less than those at s2 , then memcmp returns a negative number; if the bytes at s1 are lexicographically greater than those at s2 , then memcmp returns a positive number; otherwise they are equal, and memcmp returns 0.